委買賣差語法

想請問這個數字，語法應該怎麼寫呢？

如果我要寫成買賣差>1000時進場，買賣差<1000時出場，語法是這樣子寫嗎?

 //進場

Value1 = GetQuote("累計委買");

Value1 = GetQuote("BidUnits");

Value1 = GetQuote("即時委買張數");

Value1 = q_BidUnits;

Value2 = GetQuote("累計委賣");

Value2 = GetQuote("AskUnits");

Value2 = GetQuote("即時委賣張數");

Value2 = q_AskUnits;

Value3 = Value1- Value2;

if Value3>1000 then ret=1;

//出場

Value1 = GetQuote("累計委買");

Value1 = GetQuote("BidUnits");

Value1 = GetQuote("即時委買張數");

Value1 = q_BidUnits;

Value2 = GetQuote("累計委賣");

Value2 = GetQuote("AskUnits");

Value2 = GetQuote("即時委賣張數");

Value2 = q_AskUnits;

Value3 = Value1- Value2;

if Value3<1000 then ret=1;

但這樣子寫，跑回測的時候都不會有成交單，不曉得是哪裡出錯了？